■/,•'• 



Table 28. Plants 



that recove 



red from overwash 



aft' 



ar 1 year. 



Species 



Hnx 



• reco 



rded 



Species 





Max 



. recorded 





bur 



iel de 



pth 







bur 



lal depth 

 (cm) 



Ammophila breviligulata 





59.0 





Salicomia virginica 







10.0 



Artemisia etelleriana 





53.0 





Scirpua americana 







30.0 



Baocharia halimifolia 





54.0 





Solidago sempervirena 







56.0 



Juniperue lirginiana 





75.0 





Spartina dlterniflora 







30.0 



Lathyrua japonicua 





43.0 





Spartina patens (upright) 





42.5 



Limonium nashii 





10.0 





Spartina patens (decumbent) 





33.0 



Myriea peneylvanica 





45.0 





Teucrium canader.se 







25.0 



Roaa rugoaa 





65.0 





Typha latifolia 







20.0 



'shrub, not coepletely 



burl 



ed by 



over* 



'ash deposit. 









NOTE. — Data froo the Sumner of 1978. Ammophila breviligulata, Artemisia etel- 

 leriana , Lathyrue japonicUB, Solidago sempervirens, Spartina alterniflora and 

 Spartina patens data froa 1977-78 sampled plots. Other depths selected from 

 vaehover deposits ar*? not within a study area. Ail recovered burial depths 

 should be taken as low values. 



that continue to accrete at a high annual rate. Other shrubs, Baccharis 

 halimi folia (groundsel tree) (54 centimeters) and Juniperue virginiara (red 

 cedar) (75 centimeters), found in the stable zone between the dune community 

 and the hi^h marsh community on many northeast barrier beaches, were surpris- 

 ingly able to recover from high levels of burial. A total of 14 species of 

 flowering plants and 1 gymaosperm were able to recover from 10 centimeters or 

 more of overwash burial at the Nauset Spit (Nauset Spit-Eastham and North 

 Beach) after 1 year. 



5. Colonization of Washovers . 



a. Introduction . Daring major storms, overwash surges transport sediment 

 across the entire barrier with deposition in the adjacent lagoon. These 

 deposits represent new supratidal and intertidal environments that may be 

 colonized by vegetation and are important in landward barrier migration. On 

 Nauset Spit-Eastham, almost 2 hectare^ of new substrata was emplaced along the 

 back barrier margin as a result of the February 1978 stona. 



Washover sand is more often deposited on previously vegetated surfaces. 

 After storms, sand-dune vegetation not eroded by overwash surges can recover 

 from burial. Ammophila breviligulata plants, buried by as much as 67 centi- 

 meters of sand, recovered rapidly, early in the growing season. Overwash and 

 aeolian burial actually lead to an increase in Ammophila breviligulata bio- 

 mass. Salt-marsh plants buried by shallow deposits can also recover, although 

 washover deposition in the northeast often exceeds plant recovery capability. 

 During the February 1978 storm, sand deposits as deep as 165 centimeters 

 accumulated on old marsh surfaces, resulting in large, barren, flat washovers 

 on Nauset Spit-Eastham. 



An analysis of historical aerial photography (see Sec. IV) suggests that 

 these initially barren areas are rapidly colonized by either salt-aarsh or 

 sand-dune vegetation. Photos taken soon after the 1938 hurricane showed large 

 barren washovers along North Beach. These features were still evident in 

 1952 but were covered by sand dunes and salt marshes. In December 1972 a 



120 



